On 14/04/14 17:51, David Miller wrote: > From: David Vrabel <david.vra...@citrix.com> > Date: Mon, 14 Apr 2014 10:42:20 +0100 > >> On 12/04/14 21:51, David Miller wrote: >>> From: Vincenzo Maffione <v.maffi...@gmail.com> >>> Date: Sat, 12 Apr 2014 11:55:40 +0200 >>> >>>> This patch fixes the initialization of an array used in the TX >>>> datapath that was mistakenly initialized together with the >>>> RX datapath arrays. An out of range array access could happen >>>> when RX and TX rings had different sizes. >>>> >>>> Signed-off-by: Vincenzo Maffione <v.maffi...@gmail.com> >>> >>> Good catch, applied, thanks. >> >> Thanks. You can queue this for net-next since the Tx and Rx rings are >> the same constant size. > > I was able to determine when I reviewed this patch that the size in bytes > of the rings are the same (PAGE_SIZE), but I couldn't ascertain whether > the individual ring entries in the TX ring and RX ring are the same size. > > Are they?
Yes. It's not at all obvious, but each ends up with 256 entries. Tx entries are 12 bytes and Rx entries are 8 bytes. The ring macros reserve some space in the shared page for the producer/consumer indexes /and/ round down the number to the next power of two. David -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
